An illustration of the “classic” effects of post-training hippocampal lesions for rats trained on a 40-s peak-interval procedure. The peak functions of rats with hippocampal lesions (HPX) rats are shifted leftward relative to control (CON) rats and are sharper with less spread around the observed peak time. Data are replotted from Buhusi et al. ().

Diagrams of three possible mappings of functional hippocampal connectivity within the neural circuits proposed by the striatal beat-frequency (SBF) model of interval timing: (A) the hippocampus is involved in a feedback mechanism designed to update temporal expectancy with a separate cortical area. This area's output is then integrated with clock and reward information by striatal medium spiny neurons (MSNs). (B) The hippocampus modulates MSN firing thresholds via either tonic inhibition or phasic excitation. (C) Hippocampal regulation downstream of the MSNs affects translation of temporal information into motor output.